Nice. Is there a way to edit the animation curve directly on the graph? Also, I edited the CSS and I can see the animation changing but the graph doesn't update.
Editing bezier curves control points on the graph will be in the next update. Currently the timeline click+drag controls support adjusting duration and delay of the animations.
Editing the CSS should update the graphs automatically. Make sure you're looking at the correct keyframe & selector combination. If it doesn't update that's a bug send me an email, I'd like to know!
I can only edit the duration and delay.